Add 81/21 and 20/24
1st number: 3 18/21, 2nd number: 20/24
81/21 + 20/24 is 197/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
81/21 = 81 × 8/21 × 8 = 648/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
20/24 = 20 × 7/24 × 7 = 140/168 - Add the two like fractions:
648/168 + 140/168 = 648 + 140/168 = 788/168 - 788/168 simplified gives 197/42
- So, 81/21 + 20/24 = 197/42
In mixed form: 429/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/21+40/24 81/42+20/24 81/21+20/48 81/21+60/24 81/63+20/24 81/21+20/72